Two reasons why what these people are doing won't work firstly they are singing the wrong note they have to find out what frequency this glass naturally resonates at (by tapping it maybe) then sing that note. Also if the glass is just made of ordinary glass this won't work; the glass must me made of crystal as crystal resonates more easily.

I don't think my voice broke the dishes. I think the chamber amplified my voice and caused one of the metal rods of the upper rack to vibrate. All of the various dishes that broke were in contact with the one metal rod.

Ten years ago, while loading the dishwasher, I thought the kids should be helping. Knowing they were scattered around the house, and hearing loud music in the basement, I knew it would take a lot of sound to get their attention. Fortunately (?) I have a deep resonant voice, and I felt up to the challenge. I shouted with a sort-of singing resonance as I stuck my head in the dishwasher to make room for another dish. Suddenly, ALL of the glass on the top rack shattered, raining glass shards.

In my case, I think I hit the frequency of the metal rack the dishes were on, because the dishes that broke were all kinds of shapes and sizes. Some large drinking glasses shattered, a couple of small juice glasses shattered, and all of the glass stemware shattered. The common characteristic was that they were all fragile.